Side effects of radiotherapy

Find out about the side effects of external radiotherapy to the lung and how to cope with them.

Side effects tend to start a week after the radiotherapy begins. They gradually get worse during the treatment and for a couple of weeks after the treatment ends. But they usually begin to improve after around 2 weeks or so.

These side effects vary from person to person. You may not have all of the effects mentioned.

You might feel tired during your treatment. It tends to get worse as the treatment goes on. You might also feel weak and lack energy. Rest when you need to.

Tiredness can carry on for some weeks after the treatment has ended but it usually improves gradually.

Various things can help you to reduce tiredness and cope with it, such as exercise. Some research has shown that taking gentle exercise can give you more energy. It's important to balance exercise with resting.

Your skin might go red or darker in the treatment area. You might also get slight redness or darkening on the other side of your body. This is where the radiotherapy beams leave the body.

The red or darker areas can feel sore. Your radiographers will give you creams to soothe your skin. The soreness usually goes away within 2 to 4 weeks of ending the treatment. But your skin might always be slightly darker in that area.

Radiotherapy to the chest area might cause some inflammation of your lungs. Soon after the treatment, you might have a dry cough or shortness of breath. This is called acute radiation pneumonitis (pronounced new-mon-eye-tiss).

You might find that having a soft diet is easier to swallow until a few weeks after your treatment is over. Foods such as soups and stews are easier to swallow than more solid foods like meat or toast.

Your radiotherapy department can give you an information sheet to help advise you.

Tell your doctor or radiographers if you have problems swallowing. They can advise you on ways to reduce this.

Ask to see a dietitian if you have problems with eating and drinking.

Tips for eating and drinking

Drink about 8 glasses of water a day while having treatment.

Make sure that you eat slowly and avoid eating late in the day.

Drink plenty during and after meals to soften your food.

Eat small amounts often rather than big meals.

Try different foods to find out which are easiest to swallow.

You can have high calorie drinks to boost your calorie intake if you need them.

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